TIF, you're right about the reverse, the Tet is far superior primarily because the celator had a larger area to work with. Regardless, the mismatch in size is annoying. My focus on acquiring a nice Parthian coin was the portrait. The larger coin not only has missing detail in the hair but also on the high point of the shoulder.
Pellinore, your drachma of Mithradates II is a little gem. I love the ostentatious crown, & the toning on the coin accentuates the detail on both sides.